The present invention relates to a sprinkler.
Sprinklers are used in orchards to water fruit trees. A number of sprinklers are installed in an orchard to water all its fruit trees.
In case of an orchard lying on a slope of a hill, a large number of fruit trees vegetate extensively, requiring many sprinklers. The initial investment for them is costly and their installation is laborious.
Introduced in recent years to solve the above problems has been a sprinkler shown in FIG. 6, which is constructed by laying and connecting pipes of vinyl chloride on the ground between fruit trees and fitting the pipeline with a plurality of sprinkler heads.
As shown in FIG. 6, through holes 100h are made in the top portion of the wall of each pipe and a nozzle is set in each through hole 100h. Each nozzle comprises a cylindrical part 111 and an axial part 112 inserted in the cylindrical part 111. A through hole 111h is made in the side wall of the cylindrical part 111. A gap to let water through is provided between the inner surface of the cylindrical part 111 and the outer surface of the axial portion 112a of the axial part 112.
Accordingly, when water is allowed to run through the pipeline, the water flows into the cylindrical part 111 through its through hole 111h of each nozzle, flows further through the gap between the inner surface of the cylindrical part 111 and the outer surface of the axial portion 112a of the axial part 112, and spouts out from the gap 110s between the head of the cylindrical part 111 and the head 112b of the axial part 112. Thus, the water running in the pipeline is fed to nearby fruit trees.
Because the pipes 100 of the above sprinkler are fixed on the ground, nozzles 110 cannot be redirected to desired fruit trees. Accordingly, water is fed to nearby fruit trees by sprinkling water in all directions from each nozzle. In this case, however, water is fed not only to places where fruit trees is planted but also to places where no fruit trees are planted. Thus, water is sprinkled inefficiently.
On the other hand, it is desirable to sprinkle water on the whole of a grown-up fruit tree, whereas it is desirable to feed water mainly to the root area of a nursery tree. Besides, the quantity of water required by a nursery tree and that required by a grown-up tree are different from each other; therefore, as a fruit tree grows, the quantity of water to be fed and the place to be fed with water have to be adjusted. In the case of the above sprinkler, places to be fed with water are adjusted by adjusting the water pressure in the pipeline and gaps 110s. Such adjustment is difficult; therefore, it is difficult to feed desired places with water.
If individual pipes can be turned around their respective longitudinal axial centers, places to be fed with water can easily be adjusted. However, pipes are fixedly connected to each other with adhesive or other means. If some pipes are to be turned, they have to be disconnected from their immediately upstream and downstream pipes, which is laborious. If pipes are connected to each other so as to be easily disconnectable from each other, relative turning at the connections between pipes cannot be prevented completely. Accordingly, while water is being sprinkled, pipes turns, changing the directions of sprinkler heads and, thereby, shifting the places where sprinkled water lands. Under the circumstances, a method of adjusting places to be sprinkled with water has not been developed yet.